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The compression shearing method is used for consolidating commercially available Nd-Fe-B melt-spun ribbons (MQ powders) at temperatures ranging from room temperature to 573 k. The bulk material consolidated at room temperature is magnetically isotropic, whereas the bulk material consolidated at 573 K is magnetically anisotropic.

The scanning Hall probe microscopy technique is employed for a complete magnetic characterization of the different magnetic fields that are produced by the Nd-Fe-B hard magnetic fields. The application of the length-scales of the films for the employment of the micromagnet arrays for lab-on-chip applications is also analyzed.

Bulk [alpha]-Fe/[Nd.sub.2][Fe.sub.14]B nanocomposite magnets with a maximum energy product up to 17.5 MG Oe are produced by using [Nd.sub.9][Fe.sub.85][B.sub.6] with a few [alpha]-Fe crystallites in an amorphous matrix as precursors with a combination of plastic deformation at room temperature and thermal annealing. A high volume faction is achieved for soft-magnetic phase in the deformation-processed bulk magnets, leading to enhanced magnetic properties in the magnets as compared with those fabricated from nondeformed ribbons.

Several analyses of the hysteresis curves are conducted to explain the magnetization reversal behavior exhibited by the high coercivity Zr doped [alpha]-Fe/[Nd.sub.2][Fe.sub.14]B nanocomposite alloys.

The microstructure of the grain boundary and the chemistry observed in the various Dy-diffusion processed Nd-Fe-B sintered magnets is discussed. The various mechanisms exhibited by the coercivity enhancement techniques of these magnets are also explained.

Several studies are conducted to explain the magnetic properties of the various Nd-Fe-B film magnets, which are usually synthesized via the arc deposition technique. The films are shown to exhibit a highly amorphous structure.

The article presents a new methodology, which can be easily employed for determining the initial flux of the anisotropic NdFeB/SmFeN hybrid magnets. The demagnetization curves at room temperature and the exposure temperatures of the hybrid magnets are shown to be the main determinants of the initial flux loss of the magnets.

The impact of temperature on the spontaneous remagnetization observed in the various [Nd.sub.60][Fe.sub.30][Al.sub.10] and [Nd.sub.60][Fe.sub.20][Co.sub.10][Al.sub.10] bulk amorphous ferromagnets is discussed. The spontaneous remagnetization measure is shown to increase linearly with the temperature.

Several magnetic measurements and electron microprobe analyses are conducted to explain the microstructures, as well as the magnetic properties of the various sintered MR[E.sub.2][Fe.sub.14]B magnets (MRE = Y+Dy+Nd). Composition segregation of grains is shown to lead to the higher temperature coefficients in these magnets.

The article discusses the development of a new process, which can be used for the coercivity enhancement of the sintered [Nd.sub.14.4][Fe.sub.78.4][Co.sub.1.3][B.sub.5.9] magnets by dysprosium diffusion in grain boundaries of rapidly solidified strips. The technique is shown to lead to a significant enhancement in the energy products of the magnets.

Numerous studies are conducted to explain the preparation, microstructure and the magnetic properties of the various hot deformed NduFeuB ring magnets. The changes taking place in the magnetic properties along the axis are also analyzed.

The article explains the domain structure, as well as the magnetization process employed in the hydrogenation disproportionation desorption recombination processed NduFeuB powder. The domain wall pinning effect is shown to lead to extremely high coercivity of these compounds.

The article explains the structure, as well as the various magnetic properties of the different isotropic and anisotropic Nd-Fe-B permanent magnets that are prepared by the spark plasma sintering technology. The various effects of the processing conditions and deformation height reduction on these properties are also discussed.

A giant magnetoelectric (ME) effect observed in a current-to-voltage (I-to-V) conversion device formed by sandwiching a PZT piezoelectric cymbal transducer between an NdFeB magnet and a Fe-core solenoid is reported. The observed ME effect and the resulting I-to-V conversion in the device is demonstrated by a physical model based on the combination of electromagnetomechanics in the magnet-solenoid assembly and amplified piezoelectricity in the cymbal transducer.

The complete phase diagram of NdFeAs[O.sub.1-x][F.sub.x] solid solution is provided as a function of electron doping by the determination of F- and O-content and phase content. The method has indicated that in order to provide reliable results on the complex new superconducting materials, a rigorous control of the chemical composition of the phase is carried out.

The article explains a new approach, which employs the hot-deformation processing of the amorphous alloys for the preparation of the various bulk anisotropic [Nd.sub.2][Fe.sub.14]B/[alpha]-Fe nanocomposite magnets. A new strategy for improving the texture of the compounds is also presented.

Nanocomposite [alpha]-Fe/[Nd.sub.2][Fe.sub.14]B alloys with high coercivity are prepared by melt spinning and the impact of Ti addition on the microstructure and magnetic properties of these nanocomposite alloys are examined. The Kronmuller plot has provided evidence for a reduction in the exchange coupling that has resulted in an increase in the coercivity.

The [([Fe.sub.0.25][Nd.sub.0.75]).sub.0.6][B.sub.0.4] amorphous nanoparticles were prepared in dispersed (polymeric matrix) and powder systems to explore internal magnetic order of the particles and the effects arising from the interactions among them. The observed interparticle interactions were found to affect primarily the surface spins and induce a decrease in the total magnetization of the particle.

A chemical solution deposition was applied to grow BiFeO3/Bi3.15Nd0.85Ti3O12 (BFO/BNdT) multilayer films on Pt-coated silicon substrate. A comprehensive study provided insight into structural ferroelectric, dielectric, and magnetic properties of multilayer films.

The electronic structure and magnetic moment of [Nd.sub.2][Fe.sub.14]B and [Dy.sub.2][Fe.sub.14]B are calculated by using the linear-combination-of-localized-pseudo-atomic-orbital (LCPAO) method. The magnetic moments of iron atoms in [Nd.sub.2][Fe.sub.14]B are increased by spin-orbit interaction and the magnetic moment calculation obtained by LCPAO is suitable for large-scale systems with rare-earth elements.

The magnetic properties of pulsed laser deposition (PLD)-made anisotropic films with Ga additive are evaluated. The magnetic properties are superior when compared to those of the anisotropic PLD-made Nd-Fe-B films without additives and the peak intensities of x-ray diffraction patterns corresponding to c-planes of the film with Ga addition are stronger than those of the additive-free film.

The electronic structures of a (001) surface of crystalline [Nd.ub.2][Fe.sub.14]B are studied by using a slab model and the crystal field parameters are estimated at Nd sites based on site principles calculations. The results have shown that Nd ions located around the (001) surfaces of crystalline [Nd.sub.2][Fe.sub.14]B would be nucleation sites of reversed magnetic domains.

The effect of oxygen on the surface coercivity of Nd-coated Nd-Fe-B sintered magnets is examined in order to understand the coercivity mechanism. The studies have shown that certain amount of oxygen is an essential ingredient to obtain a high coercivity in Nd-Fe-B sintered magnets.

The devitrification behavior of nanocrystalline MR[E.sub.2][(Fe,Co).sub.14]B+ZrC (MRE=Nd+Y+Dy) is analyzed by using differential scanning calorimetry (DSC) and analytical transmission electron microscopy (TEM) methods. The partitioning behavior of various elements at different annealing conditions is associated with changes in magnetic properties, which has led to an improved optimum microstructure.

Surfactant-assisted ball milling and subsequent size-selection method are used for preparing Nd-Fe-B nanoparticles. The structural analysis has shown that nanoparticles with two particle sizes are obtained and the partially amorphous Nd-Fe-B nanoparticles have given their room-temperature coercivities around 0.1 and 1.5 kOe for the small and large nanoparticles.

The effect of Nd[F.sub.3], Dy[F.sub.3] and Ca[F.sub.2] additions on the electrical resistivity and magnetic properties of Pr-Fe-B hot-pressed and die-upset permanent magnets is examined. The addition of fluorides has increased the resistivity of the hot-pressed specimens, whereas the resistivity of the die-upset specimens measured perpendicularly to the direction of the applied force is only slightly increased when compared to the magnet counterparts without the fluoride addition.

Polarization curve and electrochemical impedance spectroscopy tests are used for examining the corrosion kinetics for both spark plasma sintered (SPS) and conventional sintered Nd-Fe-B magnets in different electrolytes. The studies have shown that the unique microstructure in SPS magnets has restrained the aggressive intergranular corrosion taking place along Nd-rich phases in conventional magnets.

High resolution scanning electron microscopy and transmission electron microscopy are used for examining the microstructure of hydrogenation disproportionation desorption recombination processed powders with a nominal composition of [Nd.sub.12.5][Fe.sub.73][Co.sub.8][B.sub.6.5]. The Lorenz observation of the magnetic domain motion of various stages of the desorption recombination stage has shown that domain walls are strongly pinned by Nd-enriched grain boundaries in high coercivity powder.

The pressure dependence of the growth of [alpha]-Fe and [Nd.sub.2][Fe.sub.14]B nanocrystals in amorphous [Nd.sub.9][Fe.sub.85][B.sub.6] is measured. The studies have shown that the growth of nanocrystals is dependent on atomic diffusion mediated by vacancy-type thermal defects.